Biphenyloxyacetic acid derivatives for the treatment of respiratory disease

ABSTRACT

The invention relates to substituted phenoxyacetic acids as useful pharmaceutical compounds for treating respiratory disorders, pharmaceutical compositions containing them, and processes for their preparation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/973,395, filed Dec. 20, 2010, which is a continuation of U.S.application Ser. No. 12/089,276, filed Apr. 4, 2008 now U.S. Pat. No.8,008,350, which is the U.S. National Stage under 35 U.S.C. §371 ofInternational Application No. PCT/GB2006/003697, filed Oct. 5, 2006,which claims the benefit of United Kingdom Application Serial No.0520324.5, filed Oct. 6, 2005; United Kingdom Application Serial No.0525082.4, filed Dec. 9, 2005; and United Kingdom Application Serial No.0602800.5, filed Feb. 11, 2006; each of these prior applications isincorporated herein by reference in its entirety.

The present invention relates to substituted phenoxyacetic acids asuseful pharmaceutical compounds for treating respiratory disorders,pharmaceutical compositions containing them, and processes for theirpreparation.

WO2004089884 and WO2004089885 disclose a series of phenoxyacetic acidsthat are active at the CRTh2 receptor. It has now been found thatcertain compounds within the generic scopes of WO2004089884 andWO2004089885, but not specifically disclosed therein, exhibitsurprisingly high potency at the CRTh2 receptor together with excellentpharmacokinetic properties in animal species, and as a consequence areexpected to be potentially useful for the treatment of variousrespiratory diseases, including asthma and COPD.

In a first aspect the invention therefore provides a compound of formula(I) or a pharmaceutically acceptable salt thereof:

in which:

A and D are independently selected from hydrogen, halogen, nitrile, C₁₋₃alkyl, C₁₋₃ alkoxy (the latter 2 groups can be optionally substituted byone or more halogen atoms);

X is halogen, or C₁₋₃ alkyl which is optionally substituted by one ormore halogen atoms;

Y is a bond;

Z is aryl or heteroaryl substituted by one or more selected fromhydrogen, halogen, nitrile, C₁₋₆ alkyl, C₁₋₆ alkoxy, SO₂C₁₋₆alkyl,heteroaryl; the latter four groups may be optionally substituted byhalogen atoms, nitrile or SO₂C₁₋₆alkyl;

R¹ and R² independently represent a hydrogen atom, or a C₁₋₃ alkylgroup;

or

R¹ and R² together can form a 3-8 membered ring optionally containingone or more atoms selected from O, S, NR³ and itself optionallysubstituted by one or more C₁-C₃ alkyl; and

R³ is hydrogen or C₁-C₆ alkyl.

In the context of the present specification, unless otherwise indicated,an alkyl group or an alkyl moiety in a substituent group may be linearor branched.

Aryl is defined as phenyl, napthyl or biphenyl;

Heteroaryl is defined as a 5-7 member aromatic ring or can be 6,6- or6,5-fused bicyclic ring optionally containing one or more heteroatomsselected from N, S, O. The bicyclic ring may be linked through carbon ornitrogen and may be attached through the 5 or 6 membered ring and can befully or partially saturated.

Examples include pyridine, pyrimidine, thiazole, oxazole, pyrazole,imidazole, furan, isoxazole, pyrrole, isothiazole and azulene, naphthyl,indene, quinoline, isoquinoline, indole, indolizine, benzo[b]furan,benzo[b]thiophene, 1H-indazole, benzimidazole, benzthiazole,benzoxazole, purine, 4H-quinolizine, cinnoline, phthalazine,quinazoline, quinoxaline, 1,8-naphthyridine, pteridine, quinolone and1,2-methylenedioxy benzene.

Preferably X is chloro, fluoro or methyl.

Preferably the group SO₂—Y—Z is at the 4-position of the phenyl ring:—

More preferably the group SO₂—Y—Z is at the 4-position of the phenylring, ortho to both group A and group D:—

Most preferably the group SO₂—Y—Z is at the 4-position of the phenylring, ortho to the group A and meta to the group D:—

Preferably the groups A and D are independently hydrogen, halogen orC₁₋₃ alkyl (the latter being optionally substituted by halogen atoms);more preferably A is hydrogen, halogen or CF₃; D is hydrogen, halogen ormethyl; most preferably A and D are independently selected from hydrogenand halogen.

Preferably R¹ and R² are independently hydrogen or C₁₋₃ alkyl, morepreferably hydrogen or methyl.

Preferably Y is a bond.

Preferably Z is phenyl optionally substituted by halogen or C₁₋₆ alkoxy;more preferably Z is phenyl optionally substituted by halogen; mostpreferably Z is phenyl optionally substituted by fluoro.

Preferred compounds of the invention include:

-   {[5-Chloro-4)-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid;-   {[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid;-   (2S)-2-{[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoic    acid;-   ({5-Chloro-3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)acetic    acid;-   {[2′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid;-   {[5-Chloro-2′-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic    acid;-   {[5-fluoro-4′-(phenylsulfonyl)-3′-(trifluoromethyl)biphenyl-2-yl]oxy}acetic    acid;-   (2S)-2-({5-chloro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoic    acid;-   ({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)acetic    acid;-   (2S)-2-({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoic    acid;-   (2S)-2-({3′,5-difluoro-4′-[(2-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoic    acid;-   (2S)-2-({3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)propanoic    acid;-   (2S)-2-({3′,5-difluoro-4′-[(3-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoic    acid;-   ({5-chloro-4′-[(4-fluorophenyl)sulfonyl]-2′-methylbiphenyl-2-yl}oxy)acetic    acid;-   (2S)-2-{[2′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoic    acid;-   ({3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)acetic    acid;-   ({5-chloro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)acetic    acid;-   ({4′-[(2-chlorophenyl)sulfonyl]-3′,5-difluorobiphenyl-2-yl}oxy)acetic    acid;-   (2S)-2-{[3′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoic    acid;-   ({4′-[(3-chlorophenyl)sulfonyl]-2′,5-difluorobiphenyl-2-yl}oxy)acetic    acid;-   ({2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)acetic    acid;-   {[3′-fluoro-5-methyl-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic    acid;-   {[5-chloro-3′,5′-difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic    acid    and pharmaceutically acceptable salts thereof.

Certain compounds of formula (I) are capable of existing instereoisomeric forms. It will be understood that the inventionencompasses all geometric and optical isomers of the compounds offormula (I) and mixtures thereof including racemates. Tautomers andmixtures thereof also form an aspect of the present invention.

The compound of formula (I) above may be converted to a pharmaceuticallyacceptable salt or solvate thereof, preferably a basic addition saltsuch as sodium, potassium, calcium, aluminium, lithium, magnesium, zinc,benzathine, chloroprocaine, choline, diethanolamine, ethanolamine,ethyldiamine, tertiarybutylamine, meglumine, tromethamine or procaine,or an acid addition salt such as a hydrochloride, hydrobromide,phosphate, acetate, fumarate, maleate, tartrate, citrate, oxalate,methanesulphonate or p-toluenesulphonate.

It will be appreciated by those skilled in the art that in the processesof the present invention certain functional groups in the startingreagents or intermediate compound may need to be protected by protectinggroups. Thus, the preparation of the compound of formula (I) mayinvolve, at an appropriate stage, the removal of one or more protectinggroups. The protection and deprotection of functional groups is fullydescribed in ‘Protective Groups in Organic Chemistry’, edited by T. W.F, McOmie, Plenum Press (1973), and ‘Protective Groups in OrganicSynthesis’, 3rd edition, T. W. Greene & P. G. M. Wuts,Wiley-Interscience (1999).

Compounds of formula (I) can be prepared by hydrolysis of a compound offormula (II):

in which X, A, D, Y, Z, R¹ and R² are as defined in formula (I) or areprotected derivatives. R⁴ is C₁-C₁₀ alkyl group. Suitable groups R⁴include methyl, ethyl or tert-butyl. Hydrolysis of the ester group R⁴can be carried out using routine procedures, for example treatment ofmethyl and ethyl esters with aqueous sodium hydroxide, and treatment oftert-butyl esters with acids such as trifluoroacetic acid.

Compounds of formula (II) can be prepared by reaction of a compound offormula (III) with a compound of formula (IV):

in which X, A, D, Y, Z, R¹, R² are as defined in formula (I) or areprotected derivatives. L is a suitable leaving group such as halo or anactivated alcohol, in particular chlorine, bromine or tosylate. Thereaction can be carried out in a suitable solvent such as acetonitrileor DMF using a base such as potassium carbonate or the like. L may alsobe hydroxy so that a Mitsunobu reaction may be performed with compound(II) using for example triphenylphosphine and diethyl azodicarboxylate.Compounds of formula (II) are novel and form an additional part of thisinvention.

Compounds of formula (III) can be prepared by deprotection of a compoundof formula (V):

in which X, A, D, Y and Z, are as defined in formula (I) or areprotected derivatives. R⁵ is a suitable protecting group, for examplebenzyl or C₁₋₆ alkyl, such as methyl. The protecting group R⁵ can beremoved using a suitable dealkylating agent such as BBr₃ in a suitablesolvent such as DCM or the like. If R⁵ is benzyl, then it can also beremoved using standard hydrogenation conditions, such as palladium oncharcoal in a suitable organic solvent under an atmosphere of hydrogenin a sealed vessel. Compounds of formula (V) are novel and form anadditional part of this invention.

Compounds of formula (III) and compounds of formula (V) can be preparedby reaction of a compound of formula (VI) or a compound of formula (VII)with a compound of formula (VIII) via a Suzuki coupling reactionfollowed by deprotection of R⁵:

in which X, A, D, Y and Z, are as defined in formula (I) or areprotected derivatives thereof, R⁵ as defined for compounds of formula(V). L¹ is a suitable leaving group such as halo or an activatedalcohol; suitably bromo, iodo or triflate. Compounds of formula (VI) arecommercially available or can be prepared as outlined previously inWO2004089884 and WO2004089885.

The above steps can also be reversed. For example, compounds of formula(V) can be prepared by reacting compounds of formula (VIa) with acompound of formula (VIIIa) using a suzuki coupling reaction followed byremoval of the protecting group as outlined above.

in which X, A, D, Y and Z, are as defined in formula (I) or areprotected derivatives thereof, L¹, R⁵ and R⁶ are as outlined above.

Compounds of formula (VIII) can be prepared by reacting compounds offormula (IX) with compounds of formula (X):

in which A, D, Y and Z, are as defined in formula (I) or are protectedderivatives thereof, L¹, is as outlined above.

The reaction can be carried out in a microwave at elevated temperaturesor can be performed thermally by heating a compound of formula (IX) witha compound of formula (X) at elevated temperatures such as refluxingconditions. The reactions are carried out using a Lewis acid catalyst,such as iron (III) chloride.

Compounds of formula (VIII) can also be formed as outlined below:

in which A, D and Z, are as defined in formula (I) or are protectedderivatives thereof, L¹, is a suitable leaving group as outlined above.The thiol is dimerised by reacting with sulfuryl chloride in a suitableorganic solvent such as dichloromethane at low temperatures, preferably0° C. Alternatively the thiol is dimerised by reacting withhexamethyldisilazane and DMSO in a suitable organic solvent such asacetonitrile. The disulfide product can then be reacted with arylhalides, in particular aryl iodides compounds of formula (XI) usingstandard Grignard coupling conditions. The resulting sulfide can then beoxidised using standard oxidising procedures known by those skilled inthe art, such as reacting with mCPBA in dichloromethane or the like.

Alternatively, compounds of formula (VIII) can also be formed from thedisulfide by reaction with an aniline of formula (VIV) usingdiazotisation conditions, preferably using isoamyl nitrite in a suitablesolvent such as acetonitrile or the like at elevated temperatures. Theresulting sulfide was oxidised as outlined above.

in which A, D and Z, are as defined in formula (I) or are protectedderivatives thereof, L¹, is a suitable leaving group as outlined above.

Compounds of formula (VIV) are commercially available or can be readilyprepared using literature procedures by those skilled in the art.

In a further aspect, the present invention provides the use of acompound of formula (I), a prodrug, pharmaceutically acceptable salt orsolvate thereof for use in therapy.

The compounds of formula (I) or pharmaceutically acceptable slatsthereof have activity as pharmaceuticals, in particular as modulators ofCRTh2 receptor activity, and may be used in the treatment (therapeuticor prophylactic) of conditions/diseases in human and non-human animalswhich are exacerbated or caused by excessive or unregulated productionof PGD₂ and its metabolites.

A compound of the invention, or a pharmaceutically acceptable saltthereof; can be used in the treatment of:

1. respiratory tract: obstructive diseases of the airways including:asthma, including bronchial, allergic, intrinsic, extrinsic,exercise-induced, drug-induced (including aspirin and NSAID-induced) anddust-induced asthma, both intermittent and persistent and of allseverities, and other causes of airway hyper-responsiveness; chronicobstructive pulmonary disease (COPD); bronchitis, including infectiousand eosinophilic bronchitis; emphysema; bronchiectasis; cystic fibrosis;sarcoidosis; farmer's lung and related diseases; hypersensitivitypneumonitis; lung fibrosis, including cryptogenic fibrosing alveolitis,idiopathic interstitial pneumonias, fibrosis complicatinganti-neoplastic therapy and chronic infection, including tuberculosisand aspergillosis and other fungal infections; complications of lungtransplantation; vasculitic and thrombotic disorders of the lungvasculature, and pulmonary hypertension; antitussive activity includingtreatment of chronic cough associated with inflammatory and secretoryconditions of the airways, and iatrogenic cough; acute and chronicrhinitis including rhinitis medicamentosa, and vasomotor rhinitis;perennial and seasonal allergic rhinitis including rhinitis nervosa (hayfever); nasal polyposis; acute viral infection including the commoncold, and infection due to respiratory syncytial virus, influenza,coronavirus (including SARS) and adenovirus;2. bone and joints: arthritides associated with or includingosteoarthritis/osteoarthrosis, both primary and secondary to, forexample, congenital hip dysplasia; cervical and lumbar spondylitis, andlow back and neck pain; rheumatoid arthritis and Still's disease;seronegative spondyloarthropathies including ankylosing spondylitis,psoriatic arthritis, reactive arthritis and undifferentiatedspondarthropathy; septic arthritis and other infection-relatedarthopathies and bone disorders such as tuberculosis, including Potts'disease and Poncet's syndrome; acute and chronic crystal-inducedsynovitis including urate gout, calcium pyrophosphate depositiondisease, and calcium apatite related tendon, bursal and synovialinflammation; Behcet's disease; primary and secondary Sjogren'ssyndrome; systemic sclerosis and limited scleroderma; systemic lupuserythematosus, mixed connective tissue disease, and undifferentiatedconnective tissue disease; inflammatory myopathies includingdermatomyositits and polymyositis; polymalgia rheumatica; juvenilearthritis including idiopathic inflammatory arthritides of whateverjoint distribution and associated syndromes, and rheumatic fever and itssystemic complications; vasculitides including giant cell arteritis,Takayasu's arteritis, Churg-Strauss syndrome, polyarteritis nodosa,microscopic polyarteritis, and vasculitides associated with viralinfection, hypersensitivity reactions, cryoglobulins, and paraproteins;low back pain; Familial Mediterranean fever, Muckle-Wells syndrome, andFamilial Hibernian Fever, Kikuchi disease; drug-induced arthalgias,tendonititides, and myopathies;3. pain and connective tissue remodelling of musculoskeletal disordersdue to injury [for example sports injury] or disease: arthitides (forexample rheumatoid arthritis, osteoarthritis, gout or crystalarthropathy), other joint disease (such as intervertebral discdegeneration or temporomandibular joint degeneration), bone remodellingdisease (such as osteoporosis, Paget's disease or osteonecrosis),polychondritits, scleroderma, mixed connective tissue disorder,spondyloarthropathies or periodontal disease (such as periodontitis);4. skin: psoriasis, atopic dermatitis, contact dermatitis or othereczematous dermatoses, and delayed-type hypersensitivity reactions;phyto- and photodermatitis; seborrhoeic dermatitis, dermatitisherpetiformis, lichen planus, lichen sclerosus et atrophica, pyodermagangrenosum, skin sarcoid, discoid lupus erythematosus, pemphigus,pemphigoid, epidermolysis bullosa, urticaria, angioedema, vasculitides,toxic erythemas, cutaneous eosinophilias, alopecia greata, male-patternbaldness, Sweet's syndrome, Weber-Christian syndrome, erythemamultiforme; cellulitis, both infective and non-infective; panniculitis;cutaneous lymphomas, non-melanoma skin cancer and other dysplasticlesions; drug-induced disorders including fixed drug eruptions;5. eyes: blepharitis; conjunctivitis, including perennial and vernalallergic conjunctivitis; iritis; anterior and posterior uveitis;choroiditis; autoimmune; degenerative or inflammatory disordersaffecting the retina; ophthalmitis including sympathetic ophthalmitis;sarcoidosis; infections including viral, fungal, and bacterial;6. gastrointestinal tract: glossitis, gingivitis, periodontitis;oesophagitis, including reflux; eosinophilic gastro-enteritis,mastocytosis, Crohn's disease, colitis including ulcerative colitis,proctitis, pruritis ani: coeliac disease, irritable bowel syndrome, andfood-related allergies which may have effects remote from the gut (forexample migraine, rhinitis or eczema);7. abdominal: hepatitis, including autoimmune, alcoholic and viral;fibrosis and cirrhosis of the liver; cholecystitis; pancreatitis, bothacute and chronic;8. genitourinary: nephritis including interstitial andglomerulonephritis; nephrotic syndrome; cystitis including acute andchronic (interstitial) cystitis and Hunner's ulcer; acute and chronicurethritis, prostatitis, epididymitis, oophoritis and salpingitis;vulvo-vaginitis; Peyronie's disease; erectile dysfunction (both male andfemale);9. allograft rejection: acute and chronic following, for example,transplantation of kidney, heart, liver, lung, bone marrow, skin orcornea or following blood transfusion; or chronic graft versus hostdisease;10. CNS: Alzheimer's disease and other dementing disorders including CJDand nvCJD; amyloidosis; multiple sclerosis and other demyelinatingsyndromes; cerebral atherosclerosis and vasculitis; temporal arteritis;myasthenia gravis; acute and chronic pain (acute, intermittent orpersistent, whether of central or peripheral origin) including visceralpain, headache, migraine, trigeminal neuralgia, atypical facial pain,joint and bone pain, pain arising from cancer and tumor invasion,neuropathic pain syndromes including diabetic, post-herpetic, andHIV-associated neuropathies; neurosarcoidosis; central and peripheralnervous system complications of malignant, infectious or autoimmuneprocesses;11. other auto-immune and allergic disorders including Hashimoto'sthyroiditis, Graves' disease, Addison's disease, diabetes mellitus,idiopathic thrombocytopaenic purpura, eosinophilic fasciitis, hyper-IgEsyndrome, antiphospholipid syndrome;12. other disorders with an inflammatory or immunological component;including acquired immune deficiency syndrome (AIDS), leprosy, Sezarysyndrome, and paraneoplastic syndromes;13. cardiovascular: atherosclerosis, affecting the coronary andperipheral circulation; pericarditis; myocarditis, inflammatory andauto-immune cardiomyopathies including myocardial sarcoid; ischaemicreperfusion injuries; endocarditis, valvulitis, and aortitis includinginfective (for example syphilitic); vasculitides; disorders of theproximal and peripheral veins including phlebitis and thrombosis,including deep vein thrombosis and complications of varicose veins;14. oncology: treatment of common cancers including prostate, breast,lung, ovarian, pancreatic, bowel and colon, stomach, skin and braintumors and malignancies affecting the bone marrow (including theleukaemias) and lymphoproliferative systems, such as Hodgkin's andnon-Hodgkin's lymphoma; including the prevention and treatment ofmetastatic disease and tumour recurrences, and paraneoplastic syndromes;and,15. gastrointestinal tract: Coeliac disease, proctitis, eosinopilicgastro-enteritis, mastocytosis, Crohn's disease, ulcerative colitis,microscopic colitis, indeterminant colitis, irritable bowel disorder,irritable bowel syndrome, non-inflammatory diarrhea, food-relatedallergies which have effects remote from the gut, e.g., migraine,rhinitis and eczema.16. Diseases associated with raised levels of PGD₂ or its metabolites.

Thus, the present invention provides a compound of formula (I), or apharmaceutically-acceptable salt or solvate thereof, as hereinbeforedefined for use in therapy.

Preferably the compounds of the invention are used to treat diseases inwhich the chemokine receptor belongs to the CRTh2 receptor subfamily.

Particular conditions which can be treated with the compounds of theinvention are asthma, rhinitis and other diseases in which raised levelsof PGD₂ or its metabolites. It is preferred that the compounds of theinvention are used to treat asthma.

In a further aspect, the present invention provides the use of acompound of formula (I), or a pharmaceutically acceptable salt orsolvate thereof, as hereinbefore defined in the manufacture of amedicament for use in therapy.

In a further aspect, the present invention provides the use of acompound or formula (I), or a pharmaceutically acceptable salt orsolvate thereof, as hereinbefore defined in the manufacture of amedicament for use in therapy in combination with drugs used to treatasthma and rhinitis (such as inhaled and oral steroids, inhaledβ2-receptor agonists and oral leukotriene receptor antagonists).

The invention further relates to combination therapies wherein acompound of the invention, or a pharmaceutically acceptable saltthereof, or a pharmaceutical composition or formulation comprising acompound of the invention, is administered concurrently or sequentiallyor as a combined preparation with another therapeutic agent or agents,for the treatment of one or more of the conditions listed.

In particular, for the treatment of the inflammatory diseases such as(but not restricted to) rheumatoid arthritis, osteoarthritis, asthma,allergic rhinitis, chronic obstructive pulmonary disease (COPD),psoriasis, and inflammatory bowel disease, the compounds of theinvention may be combined with agents listed below:

Non-steroidal anti-inflammatory agents (hereinafter NSAIDs) includingnon-selective cyclo-oxygenase COX-1/COX-2 inhibitors whether appliedtopically or systemically (such as piroxicam, diclofenac, propionicacids such as naproxen, flurbiprofen, fenoprofen, ketoprofen andibuprofen, fenamates such as mefenamic acid, indomethacin, sulindac,azapropazone, pyrazolones such as phenylbutazone, salicylates such asaspirin); selective COX-2 inhibitors (such as meloxicam, celecoxib,rofecoxib, valdecoxib, lumarocoxib, parecoxib and etoricoxib);cyclo-oxygenase inhibiting nitric oxide donors (CINODs);glucocorticosteroids (whether administered by topical, oral,intramuscular, intravenous, or intra-articular routes); methotrexate;leflunomide; hydroxychloroquine; d-penicillamine; auranofin or otherparenteral or oral gold preparations; analgesics; diacerein;intra-articular therapies such as hyaluronic acid derivatives; andnutritional supplements such as glucosamine.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, together with a cytokine or agonist or antagonist of cytokinefunction, (including agents which act on cytokine signalling pathwayssuch as modulators of the SOCS system) including alpha-, beta-, andgamma-interferons; insulin-like growth factor type I (IGF-1);interleukins (IL) including IL1 to 17, and interleukin antagonists orinhibitors such as anakinra; tumour necrosis factor alpha (TNF-α)inhibitors such as anti-TNF monoclonal antibodies (for exampleinfliximab; adalimumab, and CDP-870) and TNF receptor antagonistsincluding immunoglobulin molecules (such as etanercept) andlow-molecular-weight agents such as pentoxyfylline.

In addition the invention relates to a combination of a compound of theinvention, or a pharmaceutically acceptable salt thereof, with amonoclonal antibody targeting B-Lymphocytes (such as CD20 (rituximab),MRA-aIL16R and T-Lymphocytes, CTLA4-Ig, to HuMax I1-15).

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, with a modulator of chemokine receptor function such as anantagonist of CCR1, CCR2, CCR2A, CCR2B, CCR3, CCR4, CCR5, CCR6, CCR7,CCR8, CCR9, CCR10 and CCR11 (for the C—C family); CXCR1, CXCR2, CXCR3,CXCR4 and CXCR5 (for the C—X—C family) and CX₃CR1 for the C—X₃—C family.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof; with aninhibitor of matrix metalloprotease (MMPs), i.e., the stromelysins, thecollagenases, and the gelatinases, as well as aggrecanase; especiallycollagenase-1 (MMP-1), collagenase-2 (MMP-8), collagenase-3 (MMP-13),stromelysin-1 (MMP-3), stromelysin-2 (MMP-10), and stromelysin-3(MMP-11) and MMP-9 and MMP-12, including agents such as doxycycline.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and a leukotriene biosynthesis inhibitor, 5-lipoxygenase (5-LO)inhibitor or 5-lipoxygenase activating protein (FLAP) antagonist suchas; zileuton; ABT-761; fenleuton; tepoxalin; Abbott-79175; Abbott-85761;a N-(5-substituted)-thiophene-2-alkylsulfonamide;2,6-di-tert-butylphenolhydrazones; a methoxytetrahydropyrans such asZeneca ZD-2138; the compound SB-210661; a pyridinyl-substituted2-cyanonaphthalene compound such as L-739,010; a 2-cyanoquinolinecompound such as L-746,530; or an indole or quinoline compound such asMK-591, MK-886, and BAY×1005.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, and areceptor antagonist for leukotrienes (LT) B4, LTC4, LTD4, and LTE4.selected from the group consisting of the phenothiazin-3-1s such asL-651,392; amidino compounds such as CGS-25019c; benzoxalamines such asontazolast; benzenecarboximidamides such as BIIL 284/260; and compoundssuch as zafirlukast, ablukast, montelukast, pranlukast, verlukast(MK-679), RG-12525, Ro-245913, iralukast (CGP 45715A), and BAY×7195.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and a phosphodiesterase (PDE) inhibitor such as amethylxanthanine including theophylline and aminophylline; a selectivePDE isoenzyme inhibitor including a PDE4 inhibitor an inhibitor of theisoform PDE4D, or an inhibitor of PDE5.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, and ahistamine type 1 receptor antagonist such as cetirizine, loratadine,desloratadine, fexofenadine, acrivastine, terfenadine, astemizole,azelastine, levocabastine, chlorpheniramine, promethazine, cyclizine, ormizolastine; applied orally, topically or parenterally.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and a proton pump inhibitor (such as omeprazole) or agastroprotective histamine type 2 receptor antagonist.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, and anantagonist of the histamine type 4 receptor.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and an alpha-1/alpha-2 adrenoceptor agonist vasoconstrictorsympathomimetic agent, such as propylhexedrine, phenylephrine,phenylpropanolamine, ephedrine, pseudoephedrine, naphazolinehydrochloride, oxymetazoline hydrochloride, tetrahydrozolinehydrochloride, xylometazoline hydrochloride, tramazoline hydrochlorideor ethylnorepinephrine hydrochloride.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, and ananticholinergic agents including muscarinic receptor (M1, M2, and M3)antagonist such as atropine, hyoscine, glycopyrrrolate, ipratropiumbromide, tiotropium bromide, oxitropium bromide, pirenzepine ortelenzepine,

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and a beta-adrenoceptor agonist (including beta receptorsubtypes 1-4) such as isoprenaline, salbutamol, formoterol, salmeterol,terbutaline, orciprenaline, bitolterol mesylate, or pirbuterol, or achiral enantiomer thereof.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, and achromone, such as sodium cromoglycate or nedocromil sodium.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, with a glucocorticoid, such as flunisolide, triamcinoloneacetonide, beclomethasone dipropionate, budesonide, fluticasonepropionate, ciclesonide or mometasone furoate.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, with anagent that modulates a nuclear hormone receptor such as PPARs.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, together with an immunoglobulin (Ig) or Ig preparation or anantagonist or antibody modulating Ig function such as anti-IgE (forexample omalizumab).

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, andanother systemic or topically-applied anti-inflammatory agent, such asthalidomide or a derivative thereof, a retinoid, dithranol orcalcipotriol.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and combinations of aminosalicylates and sulfapyridine such assulfasalazine, mesalazine, balsalazide, and olsalazine; andimmunomodulatory agents such as the thiopurines, and corticosteroidssuch as budesonide.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof,together with an antibacterial agent such as a penicillin derivative, atetracycline, a macrolide, a beta-lactam, a fluoroquinolone,metronidazole, an inhaled aminoglycoside; an antiviral agent includingacyclovir, famciclovir, valaciclovir, ganciclovir, cidofovir,amantadine, rimantadine, ribavirin, zanamavir and oseltamavir; aprotease inhibitor such as indinavir, nelfinavir, ritonavir, andsaquinavir; a nucleoside reverse transcriptase inhibitor such asdidanosine, lamivudine, stavudine, zalcitabine or zidovudine; or anon-nucleoside reverse transcriptase inhibitor such as nevirapine orefavirenz.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and a cardiovascular agent such as a calcium channel blocker, abeta-adrenoceptor blocker, an angiotensin-converting enzyme (ACE)inhibitor, an angiotensin-2 receptor antagonist; a lipid lowering agentsuch as a statin or a fibrate; a modulator of blood cell morphology suchas pentoxyfylline; thrombolytic, or an anticoagulant such as a plateletaggregation inhibitor.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof, and aCNS agent such as an antidepressant (such as sertraline), ananti-Parkinsonian drug such as deprenyl, L-dopa, ropinirole,pramipexole, a MAOB inhibitor such as selegine and rasagiline, a comPinhibitor such as tasmar, an A-2 inhibitor, a dopamine reuptakeinhibitor, an NMDA antagonist, a nicotine agonist, a dopamine agonist oran inhibitor of neuronal nitric oxide synthase), or an anti-Alzheimer'sdrug such as donepezil, rivastigmine, tacrine, a COX-2 inhibitor,propentofylline or metrifonate.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, and an agent for the treatment of acute or chronic pain, suchas a centrally or peripherally-acting analgesic (for example an opioidor derivative thereof), carbamazepine, phenyloin, sodium valproate,amitryptiline or other anti-depressant agent-s, paracetamol, or anon-steroidal anti-inflammatory agent.

The present invention further relates to the combination of a compoundof the invention, or a pharmaceutically acceptable salt thereof,together with a parenterally or topically-applied (including inhaled)local anaesthetic agent such as lignocaine or a derivative thereof.

A compound of the present invention, or a pharmaceutically acceptablesalt thereof, can also be used in combination with an anti-osteoporosisagent including a hormonal agent such as raloxifene, or a biphosphonatesuch as alendronate.

The present invention still further relates to the combination of acompound of the invention, or a pharmaceutically acceptable saltthereof, together with a: (i) tryptase inhibitor; (ii) plateletactivating factor (PAF) antagonist; (iii) interleukin converting enzyme(ICE) inhibitor; (iv) IMPDH inhibitor; (v) adhesion molecule inhibitorsincluding VLA-4 antagonist; (vi) cathepsin; (vii) kinase inhibitor suchas an inhibitor of tyrosine kinase (such as Btk, Itk, Jak3 or MAP, forexample Gefitinib or Imatinib mesylate), a serine/threonine kinase (suchas an inhibitor of a MAP kinase such as p38, INK, protein kinase A, B orC, or IKK), or a kinase involved in cell cycle regulation (such as acylin dependent kinase); (viii) glucose-6 phosphate dehydrogenaseinhibitor; (ix) kinin-B.sub1.- or B.sub2.-receptor antagonist; (x)anti-gout agent, for example colchicine; (xi) xanthine oxidaseinhibitor, for example allopurinol; (xii) uricosuric agent, for exampleprobenecid, sulfinpyrazone or benzbromarone; (xiii) growth hormonesecretagogue; (xiv) transforming growth factor (TGFβ); (xv)platelet-derived growth factor (PDGF); (xvi) fibroblast growth factorfor example basic fibroblast growth factor (bFGF); (xvii) granulocytemacrophage colony stimulating factor (GM-CSF); (xviii) capsaicin cream;(xix) tachykinin NK.sub1. or NK.sub3. receptor antagonist such asNKP-608C, SB-233412 (talnetant) or D-4418; (xx) elastase inhibitor suchas UT-77 or ZD-0892; (xxi) TNF-alpha converting enzyme inhibitor (TACE);(xxii) induced nitric oxide synthase (iNOS) inhibitor; (xxiii)chemoattractant receptor-homologous molecule expressed on TH2 cells,(such as a CRTH2 antagonist); (xxiv) inhibitor of P38; (xxv) agentmodulating the function of Toll-like receptors (TLR), (xxvi) agentmodulating the activity of purinergic receptors such as P2X7; or (xxvii)inhibitor of transcription factor activation such as NFkB, API, orSTATS.

A compound of the invention, or a pharmaceutically acceptable saltthereof, can also be used in combination with an existing therapeuticagent for the treatment of cancer, for example suitable agents include:

(i) an antiproliferative/antineoplastic drug or a combination thereof,as used in medical oncology, such as an alkylating agent (for examplecis-platin, carboplatin, cyclophosphamide, nitrogen mustard, melphalan,chlorambucil, busulphan or a nitrosourea); an antimetabolite (forexample an antifolate such as a fluoropyrimidine like 5-fluorouracil ortegafur, raltitrexed, methotrexate, cytosine arabinoside, hydroxyurea,gemcitabine or paclitaxel); an antitumour antibiotic (for example ananthracycline such as adriamycin, bleomycin, doxorubicin, daunomycin,epirubicin, idarubicin, mitomycin-C, dactinomycin or mithramycin); anantimitotic agent (for example a vinca alkaloid such as vincristine,vinblastine, vindesine or vinorelbine, or a taxoid such as taxol ortaxotere); or a topoisomerase inhibitor (for example anepipodophyllotoxin such as etoposide, teniposide, amsacrine, topotecanor a camptothecin);(ii) a cytostatic agent such as an antioestrogen (for example tamoxifen,toremifene, raloxifene, droloxifene or iodoxyfene), an oestrogenreceptor down regulator (for example fulvestrant), an antiandrogen (forexample bicalutamide, flutamide, nilutamide or cyproterone acetate), aLHRH antagonist or LHRH agonist (for example goserelin, leuprorelin orbuserelin), a progestogen (for example megestrol acetate), an aromataseinhibitor (for example as anastrozole, letrozole, vorazole orexemestane) or an inhibitor of 5α-reductase such as finasteride;(iii) an agent which inhibits cancer cell invasion (for example ametalloproteinase inhibitor like marimastat or an inhibitor of urokinaseplasminogen activator receptor function);(iv) an inhibitor of growth factor function, for example: a growthfactor antibody (for example the anti-erbb2 antibody trastuzumab, or theanti-erbb1 antibody cetuximab [C225]), a farnesyl transferase inhibitor,a tyrosine kinase inhibitor or a serine/threonine kinase inhibitor, aninhibitor of the epidermal growth factor family (for example an EGFRfamily tyrosine kinase inhibitor such asN-(3-chloro-4-fluorophenyl)-7-methoxy-6-(3-morpholinopropoxy)quinazolin-4-amine(gefitinib, AZD1839),N-(3-ethynylphenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine(erlotinib, OSI-774) or6-acrylamido-N-(3-chloro-4-fluorophenyl)-7-(3-morpholinopropoxy)quinazolin-4-amine(CI 1033)), an inhibitor of the platelet-derived growth factor family,or an inhibitor of the hepatocyte growth factor family;(v) an antiangiogenic agent such as one which inhibits the effects ofvascular endothelial growth factor (for example the anti-vascularendothelial cell growth factor antibody bevacizumab, a compounddisclosed in WO 97/22596, WO 97/30035, WO 97/32856 or WO 98/13354), or acompound that works by another mechanism (for example linomide, aninhibitor of integrin αvβ3 function or an angiostatin);(vi) a vascular damaging agent such as combretastatin A4, or a compounddisclosed in WO 99/02166, WO 00/40529, WO 00/41669, WO 01/92224, WO02/04434 or WO 02/08213;(vii) an agent used in antisense therapy, for example one directed toone of the targets listed above, such as ISIS 2503, an anti-rasantisense;(viii) an agent used in a gene therapy approach, for example approachesto replace aberrant genes such as aberrant p53 or aberrant BRCA1 orBRCA2, GDEPT (gene-directed enzyme pro-drug therapy) approaches such asthose using cytosine deaminase, thymidine kinase or a bacterialnitroreductase enzyme and approaches to increase patient tolerance tochemotherapy or radiotherapy such as multi-drug resistance gene therapy;or(ix) an agent used in an immunotherapeutic approach, for example ex-vivoand in-vivo approaches to increase the immunogenicity of patient tumourcells, such as transfection with cytokines such as interleukin 2,interleukin 4 or granulocyte-macrophage colony stimulating factor,approaches to decrease T-cell anergy, approaches using transfectedimmune cells such as cytokine-transfected dendritic cells, approachesusing cytokine-transfected tumour cell lines and approaches usinganti-idiotypic antibodies.

In a still further aspect, the present invention provides the use of acompound of formula (I), or a pharmaceutically acceptable salt orsolvate thereof, as hereinbefore defined in the manufacture of amedicament for the treatment of human diseases or conditions in whichmodulation of CRTh2 receptor activity is beneficial.

In the context of the present specification, the term “therapy” alsoincludes “prophylaxis” unless there are specific indications to thecontrary. The terms “therapeutic” and “therapeutically” should beconstrued accordingly.

The invention still further provides a method of treating diseasesmediated by PGD2 or its metabolites wherein the prostanoid binds to itsreceptor (especially CRTh2) receptor, which comprises administering to apatient a therapeutically effective amount of a compound of formula (I),or a pharmaceutically acceptable salt, solvate or prodrug thereof, ashereinbefore defined.

The invention also provides a method of treating an inflammatorydisease, especially psoriasis, in a patient suffering from, or at riskof, said disease, which comprises administering to the patient atherapeutically effective amount of a compound of formula (I), Or apharmaceutically acceptable salt or solvate thereof, as hereinbeforedefined.

For the above-mentioned therapeutic uses the dosage administered will,of course, vary with the compound employed, the mode of administration,the treatment desired and the disorder indicated.

For the above-mentioned therapeutic uses the dosage administered will,of course, vary with the compound employed, the mode of administration,the treatment desired and the disorder indicated.

The compound of formula (I), prodrugs and pharmaceutically acceptablesalts and solvates thereof may be used on their own but will generallybe administered in the form of a pharmaceutical composition in which theformula (I) compound/salt/solvate (active ingredient) is in associationwith a pharmaceutically acceptable adjuvant, diluent or carrier.Depending on the mode of administration, the pharmaceutical compositionwill preferably comprise from 0.05 to 99% w (percent by weight), morepreferably from 0.05 to 80% w, still more preferably from 0.10 to 70% w,and even more preferably from 0.10 to 50% w, of active ingredient, allpercentages by weight being based on total composition.

The present invention also provides a pharmaceutical compositioncomprising a compound of formula (I), or a pharmaceutically acceptablesalt or solvate thereof, as herein before defined, in association with apharmaceutically acceptable adjuvant, diluent or carrier.

The pharmaceutical compositions may be administered topically (e.g. tothe lung and/or airways or to the skin) in the form of solutions,suspensions, heptafluoroalkane aerosols and dry powder formulations; orsystemically, e.g. by oral administration in the form of tablets,capsules, syrups, powders or granules, or by parenteral administrationin the form of solutions or suspensions, or by subcutaneousadministration or by rectal administration in the form of suppositoriesor transdermally. Preferably the compound of the invention isadministered orally.

The invention will now be illustrated by the following non-limitingexamples in which, unless stated otherwise:

(i) when given, ¹H NMR data is quoted in the form of delta values formajor diagnostic protons, given in parts per million (ppm) relative totetramethylsilane (TMS) as an internal standard;

(ii) mass spectra (MS): generally only ions which indicate the parentmass are reported, unless otherwise indicated;

(iii) the title compounds of the examples and methods were namedaccording to IUPAC rules using the ACD/name and ACD/name batch (version8.0) from Advanced Chemical Development Inc, Canada;

(iv) unless stated otherwise, reverse phase HPLC was conducted using aSymmetry, NovaPak or Ex-Terra reverse phase silica column;

(v) solvents were dried with MgSO₄ or Na₂SO₄

(vi) the following abbreviations are used:

EtOAc ethylacetate Ether diethyl ether MgSO₄ anhydrous magnesium sulfateNa₂SO₄ anhydrous sodium sulfate HCl hydrochloric acid DCMdichloromethane DMSO dimethylsulfoxide h hour MCPBA3-chloroperoxybenzoic acid (Aldrich 77% max) min minutes NaHCO₃ sodiumhydrogen carbonate TFA trifluoroacetic acid Pd(dppf)Cl₂[1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II), complexwith dichloromethane THF tetrahydrofuran NaOH sodium hydroxide RT roomtemperature

EXAMPLE 1 {[5-Chloro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid

(i) 2′-(Benzyloxy)-5′-chlorobiphenyl-4-yl phenyl sulfone

5-Chloro-2-(phenylmethoxy)phenyl]-boronic acid (prepared by the methodof WO2004089885A1) (0.5 g) in dioxan (20 ml) was treated with1-bromo-4-(phenylsulfonyl)benzene (0.57 g) prepared by the method usedin JACS (1952), 74, 394-7. Sodium carbonate (0.40 g) andpalladium(diphenylphosphinoferrocene)dichloride (0.070 g) were added andthe mixture heated to 80° C. for 16 hours. The mixture was diluted withwater, extracted with ethyl acetate, dried and evaporated under reducedpressure to give an oil. The oil was purified by chromatography onsilica eluting with isohexane/diethylether 2:1 to give the sub-titlecompound as a white solid, yield 0.9 g.

¹H NMR CDCl₃: δ 8.00-7.92 (4H, m), 7.67-7.49 (5H, m), 7.30-7.19 (7H, m),7.02-6.95 (1H, d), 5.08 (2H, s).

(ii) 5-Chloro-4′-(phenylsulfonyl)biphenyl-2-ol

The product from example 1 step (i) (0.9 g) was treated with 1.0M borontribromide in DCM (3.10 ml) in dry DCM (20 ml) and stirred at roomtemperature for 1 hour. The mixture was quenched in ice water andextracted with DCM, dried (MgSO₄) and concentrated under reducedpressure to give the sub-title compound, yield 0.9 g

MS: ESI (−ve) 343 (M−1)

(iii) tert-Butyl {[5-chloro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetate

A flask was charged with tert-butylbromoacetate (0.42 ml), dry DMF (20ml), potassium carbonate (0.36 g) and the product from example 1 step(ii) (0.9 g) and then stirred at room temperature overnight. The mixturewas quenched in water and extracted with diethylether, dried (MgSO₄) andconcentrated under reduced pressure to give an oil. The oil was purifiedby chromatography on silica eluting with isohexane/diethylether 2:1 togive the sub-title compound as a colourless oil, yield 0.6 g.

MS: ESI (+ve) 476 (M+NH₄)

(iv) {[5-Chloro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid

The title compound was prepared from the product of step (iii) (0.6 g)which was stirred in TFA/DCM (1:1, 10 ml) overnight. The mixture wasconcentrated under reduced pressure to give an oil. The residue waspurified by reverse phase HPLC, yield 0.31 g.

¹H NMR: DMSO-d6: δ 8.03-7.62 (9H, m), 7.42-7.39 (2H, m), 7.08-7.05 (1H,d), 4.74 (2H, s).

MS: ESI (−ve) 401 (M−1)

EXAMPLE 2 {[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid

(i) 4-Bromo-2-fluoro-1-(phenylsulfonyl)benzene

4-Bromo-2-fluoro-benzenesulfonyl chloride (2 g), benzene (1.3 ml) andiron (III) chloride (35 mg) were heated in a sealed tube using amicrowave at 200 Watts for 15 seconds. After cooling purification byflash column chromatography (eluent 20% EtOAc/Hexane) gave the subtitlecompound as a solid, yield 1.8 g.

¹H NMR DMSO-d6: δ 8.03-7.95 (3H, m), 7.84 (H, dd), 7.80-7.65 (4H, m)

(ii) 3′,5-Difluoro-2-methoxy-4′-(phenylsulfonyl)biphenyl

To a solution/suspension of the product from part (i) (0.55 g),5-fluoro-2-methoxy-phenylboronic acid (0.3 g) in toluene (6 ml), ethanol(4 ml) and 2M Na₂CO₃ (3 ml) was addedtetrakis(triphenylphosphine)palladium (0.05 g). The mixture was heatedto 85° C. for 3 h, concentrated under reduced pressure to give a crudematerial. The residue was suspended in water, extracted withethylacetate, washed with brine, dried (MgSO₄) and concentrated underreduced pressure. Purification using flash column chromatography (eluent10% diethylether/hexane) gave the subtitle compound, yield 0.39 g.

¹H NMR DMSO-d6: δ 8.08 (1H, t), 8.00 (2H, d), 7.81-7.55 (5H, m), 7.28(2H, m), 7.17 (1H, m), 3.77 (3H, s).

(iii) 3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-ol

The product from step ii) (0.44 g) was treated with 1.0M borontribromide in DCM (3.7 ml) in DCM (10 ml) and stirred at 0° C. for 18 h.The mixture was quenched in ice water and extracted with EtOAc; dried(MgSO₄) and concentrated in vacuo to give the sub-title compound, yield0.39 g.

¹H NMR DMSO-d6: δ 9.97 (1H, s), 8.07 (1H, t), 7.99 (2H, d), 7.80-7.60(5H, m), 7.25 (1H, m), 7.10 (1H, m), 6.96 (1H, m).

(iv) tert-Butyl{[3′,5-difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product from step (iii).

¹H NMR DMSO-d6: δ 8.09 (1H, t), 8.00 (2H, d), 7.80-7.65 (5H, m), 7.34(1H, m), 7.25 (1H, m), 7.07 (1H, m), 4.71 (2H, s), 1.37 (9H, s).

(v) {[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid

The title compound was prepared by the method of example 1 step (iv)using the product from part (iv).

¹H NMR DMSO-d6: δ 13.08 (1H, s), 8.08 (1H, t), 8.00 (2H, d), 7.80-7.66(5H, m), 7.33 (1H, m), 7.24 (1H, m), 7.09 (1H, m), 4.75 (2H, s).

MS: APCI−ve 403 (M−1)

EXAMPLE 3(2S)-2-{[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid

Diisopropyl azodicarboxylate (0.19 ml) was added to a solution of theproduct of example 2 part (iii) (250 mg), tert-butyl(R)-(+)-lactate (141mg) and triphenylphosphine (252 mg) in tetrahydrofuran (10 ml) at 0° C.After 20 minutes the ice bath was removed and the reaction stirred atroom temperature overnight. The reaction mixture was then adsorbed ontosilica and purified using flash column chromatography (eluent 10%ethylacetate/hexane) to give the subtitle compound as an oil, yield 140mg.

¹H NMR DMSO-d6: δ 8.09 (1H, t), 8.00 (2H, m), 7.81-7.66 (5H, m), 7.34(1H, m), 7.24 (1H, m), 7.02 (1H, m), 4.91 (1H, q), 1.40 (3H, d), 1.34(9H, s).

(ii)(2S)-2-{[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid

The title compound was prepared by the method of example 1 step (iv)using the product from step (i).

¹H NMR DMSO-d6: δ 8.08 (1H, t), 8.00 (2H, d), 7.80-7.67 (5H, m), 7.33(1H, m), 7.23 (1H, m), 7.02 (1H, m), 4.95 (1H, q), 1.42 (3H, d).

MS: APCI-ve 417 (M−1)

EXAMPLE 4({5-Chloro-3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)aceticacid

i) 4-Bromo-2-fluoro-1-[(4-fluorophenyl)sulfonyl]benzene

The subtitle compound was prepared by the method of example 2 step (i)using 4-bromo-2-fluorobenzenesulfonyl chloride and fluorobenzene.

¹H NMR DMSO-d6: δ 8.04 (2H, m), 7.99 (1H, t), 7.86 (1H, d), 7.75 (1H,dd), 7.51 (2H, m).

ii) 5-Chloro-3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-2-methoxybiphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and 5-chloro-2-methoxyphenyl boronic acid.

¹H NMR DMSO-d6: δ 8.1-8.05 (3H, m), 7.65-7.44 (6H, m), 7.19 (1H, d),3.78 (3H, s).

iii) 5-Chloro-3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

¹H NMR DMSO-d6: δ 10.27 (1H, s), 8.09-8.04 (3H, m), 7.7 (1H, dd), 7.63(1H, dd), 7.52 (2H, m), 7.41 (1H, d), 7.29 (1H, dd), 6.99 (1H, d).

iv)tert-butyl({5-Chloro-3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product to of step (iii).

¹H NMR DMSO-d6: δ 8.11-8.05 (3H, m), 7.73-7.66 (2H, m), 7.56-7.43 (4H,m), 7.09 (1H, m), 4.74 (2H, s), 1.38 (9H, s).

v)({5-Chloro-3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (iv).

¹H NMR DMSO-d6: δ 13.13 (1H, s), 8.10-8.05 (3H, m), 7.73 (1H, s), 7.7(1H, dd), 7.53 (2H, dt), 7.49 (1H, d), 7.44 (1H, dd), 7.11 (1H, d), 4.78(2H, s).

MS: APCI(−ve) 436 (M−1)

EXAMPLE 5 {[2′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid

i) 1-Bromo-2-fluoro-4-(phenylsulfonyl)benzene

The subtitle compound was prepared by the method of example 2 step (i)using 4-bromo-3-fluorobenzenesulfonyl chloride and benzene.

¹H NMR DMSO-d6: δ 8.04-7.97 (4H, m), 7.74 (2H, m), 7.65 (2H, m).

ii) 2,5′-Difluoro-2′-methoxybiphenyl-4-ylphenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and 5-fluoro-2-methoxyphenylboronic acid.

¹H NMR DMSO-d6: δ 8.07 (2H, m), 7.91 (1H, dd), 7.85 (1H, dd), 7.75 (1H,m), 7.7-7.61 (3H, m), 7.29 (1H, m), 7.21 (1H, dd), 7.15 (1H, dd), 3.72(3H, s).

iii) 2′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

¹H NMR DMSO-d6: δ 9.77 (1H, s), 8.06 (2H, d), 7.89 (1H, d), 7.83 (1H,d), 7.78-7.63 (4H, m), 7.12 (2H, m), 6.93 (1H, m).

iv) {[2′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid

The title compound was prepared by the methods of example 1 step (iii)and example 1 step iv) using the product of step (iii).

¹H NMR DMSO-d6: δ 12.97 (1H, s), 8.07 (2H, m), 7.91 (1H, dd), 7.85 (1H,dd) 7.77-7.64 (4H, m), 7.29-7.21 (2H, m), 7.05 (1H, dd), 4.67 (2H, s).

MS: APCI(−ve) 403 (M−1)

EXAMPLE 6{[5-Chloro-2′-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid

i) 5′-Chloro-2-fluoro-2′-methoxybiphenyl-4-yl phenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of example 5 step (i) and 5-chloro-2-methoxybenzeneboronic acid.

¹H NMR DMSO-d6: δ 8.08-8.05 (2H, m), 7.91 (1H, dd), 7.84 (1H, dd), 7.75(1H, m), 7.7-7.62 (3H, m), 7.50 (1H, dd), 7.37 (1H, d), 7.17 (1H, d),3.73 (3H, s).

ii) 5-Chloro-2′-fluoro-4′-(phenylsulfonyl)biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (i).

¹H NMR DMSO-d6: δ 10.09 (1H, s), 8.08-8.05 (2H, m), 7.89 (1H, dd), 7.83(1H, dd), 7.77-7.72 (1H, m), 7.69-7.64 (3H, m), 7.32-7.27 (2H, m), 6.96(1H, dd).

iii) {[5-Chloro-2′-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid

The title compound was prepared by the methods of example 1 step (iii)and example 1 step (iv) using the product of step (ii).

¹H NMR DMSO-d6: δ 13.02 (1H, s), 8.09-8.06 (2H, m), 7.92 (1H, dd), 7.85(1H, dd), 7.77-7.65 (4H, m), 7.46 (1H, d), 7.39 (1H, d), 7.06 (1H, d),4.7 (2H, s).

MS: APCI(−ve) 419 (M−1)

EXAMPLE 7{[5-fluoro-4′-(phenylsulfonyl)-3′-(trifluoromethyl)biphenyl-2-yl]oxy}aceticacid

i) 4-bromo-1-(phenylsulfonyl)-2-(trifluoromethyl)benzene

The subtitle compound was prepared by the method of example 2 step (i)using 4-bromo-2-(trifluoromethyl)benzenesulfonyl chloride and benzene.

¹H NMR DMSO-d6: δ 8.35 (1H, d), 8.25 (1H, dd), 8.21 (1H, d), 7.88 (2H,d), 7.76-7.72 (1H, m), 7.67-7.62 (2H, m).

ii) 5′-fluoro-2′-methoxy-3-(trifluoromethyl)biphenyl-4-yl phenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and 5-fluoro-2-methoxybenzene boronicacid.

¹H NMR DMSO-d6: δ 8.47 (1H, d), 8.12 (1H, dd), 8.09 (1H, d), 7.92 (2H,d), 7.77-7.64 (3H, m), 7.40 (1H, dd), 7.31 (1H, td), 7.20 (1H, dd), 3.78(3H, s).

iii) 5-fluoro-4′-(phenylsulfonyl)-3′-(trifluoromethyl)biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

¹H NMR DMSO-d6: δ 10.06 (1H, s), 8.47 (1H, d), 8.21-8.15 (2H, m), 7.91(2H, d), 7.77-7.62 (3H, m), 7.35 (1H, dd), 7.14 (1H, m), 6.99 (1H, dd).

iv) tert-butyl{[5-fluoro-4′-(phenylsulfonyl)-3′-(trifluoromethyl)biphenyl-2-yl]oxy}acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.47 (1H, s), 8.25 (1H, d), 8.17 (1H, m), 7.92 (2H,d), 7.74 (1H, m), 7.66 (2H, m), 7.42 (1H, m), 7.28 (1H, m), 7.13 (1H,m), 4.74 (2H, s), 1.36 (9H, s).

v){[5-fluoro-4′-(phenylsulfonyl)-3′-(trifluoromethyl)biphenyl-2-yl]oxy}aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (iv).

¹H NMR DMSO-d6: δ 13.10 (1H, s), 8.47 (1H, d), 8.31 (1H, d), 8.18 (1H,dd), 7.92 (2H, d), 7.74 (1H, m), 7.66 (2H, t), 7.42 (1H, dd), 7.28 (1H,td), 7.15 (1H, dd), 4.78 (2H, s).

MS: APCI(−ve) 453 (M−1)

EXAMPLE 8(2S)-2-({5-chloro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

i) 4-bromophenyl 4-fluorophenyl sulfone

The subtitle compound was prepared by the method of example 2 step (i)using 4-fluorobenzenesulfonyl chloride and bromobenzene.

¹H NMR DMSO-d6: δ 8.1-8.02 (2H, m), 7.94-7.82 (4H, m), 7.53-7.44 (2H,m).

ii) 5-chloro-4′-[(4-fluorophenyl)sulfonyl]-2-methoxybiphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and 5-chloro-2-methoxybenzene boronicacid.

¹H NMR DMSO-d6: δ 8.13-8.06 (2H, m), 8.00 (2H, dt), 7.73 (2H, dt),7.54-7.38 (4H, m), 7.17 (1H, d), 3.76 (3H, s).

iii) 5-chloro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

¹H NMR DMSO-d6: δ 10.14 (1H, s), 8.14-8.07 (2H, m), 8.01 (2H, d), 7.81(2H, d), 7.54-7.46 (2H, m), 7.36 (1H, d), 7.29 (1H, dd), 6.99 (1H, d).

iv) tert-butyl(2S)-2-({5-chloro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoate

The subtitle compound was prepared by the method of example 3 step (i)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.15-8.10 (2H, m), 8.03 (2H, d), 7.88 (2H, d),7.54-7.42 (4H, m), 7.03-6.99 (1H, m), 4.95 (1H, q), 1.41 (3H, d), 1.36(9H, 8).

v)(2S)-2-({5-chloro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (iv).

¹H NMR DMSO-d6: δ 8.12-8.07 (2H, m), 8.0 (2H, d), 7.87 (2H, d), 7.49(2H, t), 7.43-7.38 (2H, m), 7.0 (1H, d), 4.95 (1H, q), 1.41 (3H, d).

MS: APCI(−ve) 433 (M−1)

EXAMPLE 9({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)aceticacid

i) 1-bromo-2-fluoro-4-[(4-fluorophenyl)sulfonyl]benzene

Ferric chloride (0.5 g) was added to a mixture of4-bromo-3-fluoro-benzenesulfonyl chloride (2.5 g) and fluorobenzene (3ml) and then stirred at reflux for 18 hours. The flask was cooled toroom temperature and the residue was partitioned between aqueous NaHCO₃and DCM. The DCM layer was washed with brine, dried (MgSO₄) andevaporated under reduced pressure. The residue was recrystallised fromethanol to give buff coloured crystals.

¹H NMR DMSO-d6: δ 8.15-7.98 (4H, m), 7.76 (1H, dd), 7.56-7.46 (2H, m).

ii) 5′-chloro-2-fluoro-4-[(4-fluorophenyl)sulfonyl]-2′-methoxybiphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product to of step (i) and 5-chloro-2-methoxybenzene boronicacid.

¹H NMR DMSO-d6: δ 8.12 (2H, dddd), 7.9 (1H, dd), 7.82 (1H, dd), 7.62(1H, t), 7.51-7.44 (3H, m), 7.33 (1H, d), 7.14 (1H, d), 3.7 (3H, s).

iii) 5-chloro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

¹H NMR DMSO-d6: δ 10.12 (1H, s), 8.2-8.14 (2H, m), 7.93 (1H, dd), 7.86(1H, dd), 7.68 (1H, t), 7.52 (2H, t), 7.35-7.28 (2H, m), 6.98 (1H, d).

iv)tert-butyl({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.21-8.14 (2H, m), 7.95 (1H, dd), 7.89 (1H, dd),7.74-7.68 (1H, m), 7.58-7.41 (4H, m), 7.05 (1H, d), 4.68 (2H, s), 1.36(9H, s).

v)({5-chloro-2′-fluoro-4-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (iv).

¹H NMR DMSO-d6: δ 8.18-8.13 (2H, m), 7.94 (1H, dd), 7.86 (1H, dd),7.74-7.69 (1H, m), 7.54-7.48 (2H, m), 7.46 (1H, dd), 7.39 (1H, d), 7.06(1H, d), 4.70 (2H, s).

MS: APCI(−ve) 437 (M−1)

EXAMPLE 10(2S)-2-({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

i) tert-butyl(2S)-2-({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoate

The subtitle compound was prepared by the method of example 3 step (i)using the product of example 9 step (iii).

¹H NMR DMSO-d6: δ 8.21-8.14 (2H, m), 7.96 (1H, dd), 7.89 (1H, dd),7.78-7.73 (1H, m), 7.56-7.46 (3H, m), 7.42 (1H, d), 7.0 (1H, d), 4.88(1H, q), 1.36-1.33 (12H, m).

ii)(2S)-2-({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (ii).

¹H NMR DMSO-d6: δ 8.18-8.12 (2H, m), 7.93 (1H, dd), 7.87-7.79 (2H, m),7.53-7.47 (2H, m), 7.42 (1H, dd), 7.37 (1H, d), 6.97 (1H, d), 4.78 (1H,q), 1.31 (3H, s).

MS: APCI(−ve) 451 (M−1)

EXAMPLE 11(2S)-2-({3′,5-difluoro-4′-[(2-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

i) 1,1′-dithiobis(2-fluorobenzene)

Sulfuryl chloride (0.7 ml) was added dropwise to a solution of2-fluorobenzenethiol (1.5 ml) in DCM (20 ml) at 0° C. The reactionmixture was stirred for 30 min, then concentrated under reducedpressure. The residue was purified by chromatography on silica elutingwith isohexane to give the sub-title compound as an oil, yield 1.7 g.

MS: APCI(+ve) 254 (M+H)

ii) 4-bromo-2-fluoro-1-[(2-fluorophenyl)thio]benzene

4-Bromo-2-fluoro-1-iodobenzene (1.67 g) was added to a solution ofisopropylmagnesium chloride (2.79 ml, 2M solution in THF) in THF (8 ml),which was cooled to 0° C. and stirred for a further 2 h. The mixture wasthen added to a solution of the product of step (i) in THF (5 ml). Thereaction was allowed to reach RT overnight, then stirred at 40° C. for 1hour and 50° C. for a further 1 hour. The reaction was cooled to RT,diluted with ammonium chloride and extracted with diethylether. Thediethylether fractions were dried (MgSO₄) and evaporated under reducedpressure, yield 1.9 g. Used directly without further purification.

MS: APCI(+ve) 302 (M+H)

iii) 4-bromo-2-fluoro-1-[(2-fluorophenyl)sulfonyl]benzene

MCPBA (2.58 g) was added to a solution of the product of step ii) (1.8g) in DCM (25 ml) at 0° C. The reaction mixture was allowed to reach RTand stirred for 23 hours. The reaction was washed with aqueous sodiummetabisulfite, aqueous NaHCO₃, dried (MgSO₄) and then evaporated underreduced pressure. The residue was purified by chromatography on silicaeluting with isohexane then 4:1 isohexane/ethyl acetate to give thesub-title compound as a white solid, yield 0.71 g.

¹H NMR CDCl₃: δ 8.16 (1H, t), 8.05 (1H, t), 7.67-7.62 (1H, m), 7.53 (1H,d), 7.37 (1H, d), 7.31 (1H, d), 7.13 (1H, t).

iv) 3′,5-difluoro-4′-[(2-fluorophenyl)sulfonyl]-2-methoxybiphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (iii) and 5-fluoro-2-methoxybenzene boronicacid.

¹H NMR DMSO-d6: δ 8.12 (2H, dddd), 7.9 (1H, dd), 7.82 (1H, dd), 7.62(1H, t), 7.51-7.44 (3H, m), 7.33 (1H, d), 7.14 (1H, d), 3.7 (3H, s).

v) 3′,5-difluoro-4′-[(2-fluorophenyl)sulfonyl]biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (iv).

MS: APCI(−ve) 363 (M−H)

vi) methyl (2R)-2-{[(4-methylphenyl)sulfonyl]oxy}propanoate

A solution of methyl(R)-(+)-lactate (6.66 g) in acetonitrile (33 ml) wascooled to 5° C. and triethylamine (9.8 ml) added followed bytrimethylamine hydrochloride (0.62 g). A separate solution ofp-toluenesulfonyl chloride (11.6 g) in acetonitrile (33 ml) was addeddropwise over 20 min maintaining the temperature below 5° C. Thereaction mixture was filtered and concentrated, Diethylether and waterwere added and the organic fraction dried (MgSO₄) and concentrated invacuo to give the sub-title compound as a yellow oil (13.71 g).

¹H NMR CDCl₃: δ 7.82 (2H, d), 7.35 (2H, d), 4.95 (1H, q), 3.67 (3H, s),2.45 (3H, s), 1.51 (3H, d).

vii) methyl(2S)-2-({3′,5-difluoro-4′-[2-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoate

The product of step (v) (175 mg), the product of step (vi) (124 mg) andpotassium carbonate (133 mg) in acetonitrile (10 ml) were charged to aflask and stirred at 65° C. overnight. The reaction mixture was cooled,diluted with water (20 ml) and extracted with diethyl ether. Thecombined organic extracts were washed with brine, dried (MgSO₄) andconcentrated under reduced pressure. The residue was purified bychromatography on silica eluting with isohexane then 4:1 isohexane/ethylacetate to give the sub-title compound as a colourless oil, yield 121mg.

MS: APCI(+ve) 451 (M+H)

viii)(2S)-2-({3′,5-difluoro-4′-[(2-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

The product of step (vii) (121 mg), 1M NaOH (0.4 ml), THF (2 ml) and DCM(2 ml) were charged to a flask and stirred for 3 hours and thenconcentrated under reduced pressure. The residue was dissolved in EtOAc,washed with 1M HCl. The organic phase was dried (MgSO₄) and concentratedunder reduced pressure to give the title compound as a white solid,yield 63 mg.

¹H NMR DMSO-d6: δ 8.12 (2H, q), 7.89-7.8 (2H, m), 7.75 (1H, dd), 7.56(1H, t), 7.47 (1H, dd), 7.36 (1H, dd), 7.24 (1H, td), 7.03 (1H, dd),4.96 (1H, q), 1.43 (3H, d).

MS: APCI(−ve) 435 (M−H)

EXAMPLE 12(2S)-2-({3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

i) 4-bromo-2-fluoro-1-[(4-methoxyphenyl)sulfonyl]benzene

The subtitle compound was prepared by the method of example 9 step (i)using 4-bromo-2-fluorobenzenesulfonyl chloride and anisole.

¹H NMR DMSO-d6: δ 7.94 (1H, t), 7.89-7.85 (2H, m), 7.8 (1H, dd),7.71-7.68 (1H, m), 7.18-7.14 (2H, m), 3.84 (3H, s).

ii) 2-(benzyloxy)-3′,5-difluoro-4-[(4-methoxyphenyl)sulfonyl]biphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (iii) and[2-(benzyloxy)-5-fluorophenyl]boronic acid.

¹H NMR DMSO-d6: δ 8.01 (1H, t), 7.9 (2H, d), 7.64 (1H, dd), 7.58 (1H,dd), 7.33-7.29 (6H, m), 7.26-7.23 (2H, m), 7.2-7.16 (2H, m), 5.12 (2H,s), 3.85 (3H, s).

iii) 3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-ol

A suspension of the product of step (ii) (838 mg) in acetic acid (30 ml)and 10% Pd/C (200 mg) was stirred under 2 bar pressure of hydrogen for30 min. The catalyst was removed by filtration and the filtrate wasevaporated to give the subtitle compound, yield 630 mg.

¹H NMR DMSO-d6: δ 8.04-7.99 (1H, m), 7.91 (2H, dd), 7.68 (1H, dd), 7.6(1H, dd), 7.23 (1H, dd), 7.18 (2H, dd), 7.09 (1H, td), 6.95 (1H, dd),3.85 (3H, s).

iv) tert-butyl(2S)-2-({3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)propanoate

The subtitle compound was prepared by the method of example 3 step (i)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.08-8.02 (1H, m), 7.93 (2H, dd), 7.73 (1H, dd), 7.68(1H, dd), 7.33 (1H, dd), 7.28-7.15 (3H, m), 7.02 (1H, dd), 4.91 (1H, q),3.86 (3H, s), 1.41 (3H, d), 1.34 (9H, s).

v)(2S)-2-({3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (iv).

¹H NMR DMSO-d6: δ 8.01 (1H, t), 7.92 (2H, d), 7.86 (1H, d), 7.78 (1H,dd), 7.26 (1H, dd), 7.20-7.12 (3H, m), 6.96 (1H, dd), 4.74 (1H, q), 3.85(3H, s), 1.34 (3H, d).

MS: APCI(−ve) 447 (M−1)

EXAMPLE 13(2S)-2-({3′,5-difluoro-4′-[(3-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid

i) 1,1′-dithiobis(3-fluorobenzene)

The subtitle compound was prepared by the method of example 11 step (i)using 3-fluorobenzenethiol,

¹H NMR CDCl₃: δ 7.3-7.21 (6H, m), 6.92 (2H, tt).

ii) 4-bromo-2-fluoro-1-[(3-fluorophenyl)sulfonyl]benzene

A solution of the product of step (i) (1.98 g) and isoamyl nitrite (1.6ml) in dry acetonitrile (25 ml) was stirred at 50° C.4-bromo-2-fluoroaniline (1.23 g) was added portionwise and the reactionmixture was stirred at 60° C. for 2 h and then concentrated underreduced pressure. The residue (2.1 g) was dissolved in DCM (25 ml) andMCPBA (6 g) was added portionwise at 0° C. The reaction was stirredovernight at room temperature. The reaction was washed with aqueoussodium metabisulfite solution, aqueous NaHCO₃, dried (MgSO₄) andevaporated under reduced pressure. The residue was purified bychromatography on silica eluting with 9:1 isohexane/ethyl acetate togive the sub-title compound as a white solid (0.67 g).

¹H NMR CDCl₃: δ 7.96 (1H, td), 7.8 (1H, dq), 7.7 (1H, dq), 7.56-7.49(2H, m), 7.33 (2H, dd).

iii) 3,5′-difluoro-2′-methoxybiphenyl-4-yl 3-fluorophenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (ii) and 5-fluoro-2-methoxybenzene boronicacid.

¹H NMR CDCl₃: δ 8.10 (1H, t), 7.85 (1H, d), 7.75 (1H, d), 7.54 (1H, td),7.46 (1H, dd), 7.36-7.3 (2H, m), 7.07 (1H, ddd), 7.01 (1H, dd), 6.92(1H, dd), 3.79 (3H, m).

iv) 3′,5-difluoro-4′-[(3-fluorophenyl)sulfonyl]biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (iii).

MS: APCI(−ve) 363 (M−H)

v) methyl(2S)-2-({3′,5-difluoro-4′-[(3-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoate

The subtitle compound was prepared by the method of example 11 step(vii) using the product of step (iv) and the product of example 11 step(vi).

¹H NMR CDCl₃: δ 8.11 (1H, t), 7.86 (2H, d), 7.76 (1H, d), 7.58-7.51 (2H,m), 7.47 (1H, dd), 7.33 (1H, dd), 7.04-6.98 (2H, m), 6.82-6.77 (1H, m),4.72 (1H, q), 3.72 (3H, s), 1.51 (3H, d).

vi)(2S)-2-({3′,5-difluoro-4′-[(3-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoic acid

The title compound was prepared by the method of example 11 step (viii)using the product of step (v).

¹H NMR DMSO-d6: δ 8.1 (1H, t), 7.87-7.736 (5H, m), 7.67 (1H, td), 7.33(1H, dd), 7.24 (1H, td), 7.03 (1H, dd), 4.96 (1H, q), 1.43 (3H, d).

MS: APCI(−ve) 435 (M−H)

EXAMPLE 14({5-chloro-4′-[(4-fluorophenyl)sulfonyl]-2′-methylbiphenyl-2-yl}oxy)aceticacid

i) 4-bromo-3-methylphenyl 4-fluorophenyl sulfone

The subtitle compound was prepared by the method of example 9 step (i)using 4-bromo-3-methylbenzene sulfonyl chloride and fluorobenzene.

¹H NMR CDCl₃: δ 7.97-7.92 (2H, m), 7.77 (1H, d), 7.67 (1H, d), 7.59 (1H,dd), 7.19 (2H, t), 2.45 (3H, s).

ii) 5)-chloro-4-[(4-fluorophenyl)sulfonyl]-2′-methoxy-2-methylbiphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step i) and 5-chloro-2-methoxybenzene boronic acid.

MS: APCI(+ve) 391 (M+H)

iii) 5-chloro-4′[(4-fluorophenyl)sulfonyl]-2′-methylbiphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

MS: APCI(−ve) 375 (M−H)

iv)tert-butyl({5-chloro-4′-[(4-fluorophenyl)sulfonyl]-2′-methylbiphenyl-2-yl}oxy)acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product from step (iii).

MS: APCI(+ve) 435 (M-tBu)

v)({5-chloro-4′-[(4-fluorophenyl)sulfonyl]-2′-methylbiphenyl-2-yl}oxy)aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product from step (iv).

¹H NMR DMSO-d6: δ 8.10 (2H, ddd), 7.89 (1H, d), 7.8 (1H, dd), 7.49 (2H,tt), 7.43-7.39 (2H, m), 7.20 (1H, d), 6.99 (1H, d), 4.66 (2H, s), 2.2(3H, s).

MS: APCI−ve 447 (M−1)

EXAMPLE 15(2S)-2-{[2′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid

i) 4-bromo-3-chlorophenol phenyl sulfone

The subtitle compound was prepared by the method of example 9 step (i)using 4-bromo-3-chlorobenzenesulfonyl chloride and benzene.

¹H NMR DMSO-d6: δ 8.19 (1H, d), 8.05-8.03 (3H, m), 7.83 (1H, dd), 7.74(1H, t), 7.65 (2H, t).

ii) 2-chloro-5′-fluoro-2′-methoxybiphenyl-4-yl phenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and 5-fluoro-2-methoxybenzene boronicacid.

¹H NMR DMSO-d6: δ 8.11-8.07 (3H, m), 7.96 (1H, dd), 7.78-7.73 (1H, m),7.68 (2H, t), 7.59 (1H, d), 7.28 (1H, td), 7.16-7.11 (2H, m), 3.69 (3H,s).

iii) 2′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

¹H NMR DMSO-d6: δ 9.68 (1H, s), 8.09-8.06 (3H, m), 7.94 (1H, dd),7.77-7.72 (1H, m), 7.7-7.65 (2H, m), 7.59 (1H, d), 7.10 (1H, td), 7.02(1H, dd), 6.92 (1H, dd).

iv) text-butyl(2S)-2-{[2′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoate

The subtitle compound was prepared by the method of example 3 step (i)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.12-8.06 (3H, m), 8.019-7.95 (1H, m), 7.79-7.72 (1H,m), 7.67 (3H, t), 7.25 (1H, td), 7.17 (1H, dd), 6.95 (1H, dd), 4.77-4.68(1H, m), 1.32 (9H, s), 1.26 (3H, d).

v)(2S)-2-{[2′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid

The subtitle compound was prepared by the method of example 3 step (i)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.12-8.07 (3H, m), 7.97 (1H, dd), 7.8-7.65 (4H, m),7.21 (1H, td), 7.14 (1H, dd), 6.96 (1H, dd), 4.69-4.6 (1H, m), 1.25 (3H,d).

MS: APCI−ve 433 (M−1)

EXAMPLE 16({3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)aceticacid

i) 3-fluoro-2′-methoxy-5′-methylbiphenyl-4-yl 4-fluorophenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of example 4 step (i) and(2-methoxy-5-methylphenyl)boronic acid.

¹H NMR DMSO-d6: δ 8.10-8.03 (3H, m), 7.60 (1H, dd), 7.55-7.50 (3H, m),7.23 (1H, dd), 7.20 (1H, d), 7.04 (1H, d), 3.74 (3H, s), 2.28 (3H, s).

ii) 3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (i).

¹H NMR DMSO-d6: δ 9.71 (1H, s), 8.09-8.02 (3H, m), 7.68 (1H, dd), 7.59(1H, dd), 7.54-7.49 (2H, m), 7.16 (1H, d), 7.05 (1H, dd), 6.86 (1H, d),2.23 (3H, s).

iii)tert-butyl({3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product of step (ii).

¹H NMR DMSO-d6: δ 8.09-8.04 (3H, m), 7.69-7.63 (2H, m), 7.55-7.49 (2H,m), 7.24 (1H, d), 7.19 (1H, dd), 6.93 (1H, d), 4.67 (2H, s), 2.28 (3H,s), 1.38 (9H, s).

iv)({3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)aceticacid

The subtitle compound was prepared by the method of example 1 step (iv)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.1-8.03 (3H, m), 7.71-7.67 (2H, m), 7.55-7.49 (2H,m), 7.23 (1H, d), 7.19 (1H, dd), 6.95 (1H, d), 4.71 (2H, s), 2.27 (3H,s).

MS: APCI−ve 417 (M−1).

EXAMPLE 17({5-chloro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)acetic acid

1-bromo-4-[(4-methoxyphenyl)sulfonyl]benzene

The subtitle compound was prepared by the method of example 9 step (i)using 4-bromobenzenesulfonyl chloride and anisole.

¹H NMR DMSO-d6: δ 7.91-7.87 (2H, m), 7.86-7.80 (4H, m), 7.16-7.12 (2H,m), 3.83 (3H, s).

ii) 2-(benzyloxy)-3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and [2-(benzyloxy)-5-chlorophenyl]boronicacid.

¹H NMR DMSO-d6: δ 7.95-7.91 (4H, m), 7.77-7.74 (2H, m), 7.43 (1H, dd),7.40 (1H, d), 7.31-7.29 (5H, m), 7.23 (1H, d), 7.16-7.13 (2H, m), 5.14(2H, s), 3.83 (3H, s).

iii) 3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-ol

The subtitle compound was prepared by the method of example 12 step(iii) using the product of step (ii) and 10% Pd/C in acetic acid.

¹H NMR DMSO-d6: δ 7.95-7.89 (4H, m), 7.76 (2H, dd), 7.32 (1H, d), 7.25(1H, dd), 7.16-7.11 (2H, m), 6.97 (1H, d), 3.83 (3H, d).

iv)tert-butyl({5-chloro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product of step (iii) and tert-butyl bromoacetate which wasused directly in step (v) without further characterisation.

v) ({5-chloro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)aceticacid

The subtitle compound was prepared by the method of example 1 step (iv)using the product of step (iv).

¹H NMR DMSO-d6: δ 7.96-7.91 (4H, m), 7.81-7.78 (2H, m), 7.42-7.39 (2H,m), 7.15 (2H, dd), 7.06 (1H, dd), 4.74 (2H, s), 3.83 (3H, s).

EXAMPLE 18({4′-[(2-chlorophenyl)sulfonyl]-3′,5-difluorobiphenyl-2-yl}oxy)aceticacid

i) 1,1′-dithiobis(2-chlorobenzene)

Hexamethyldisilazane (4.4 ml) was added to a stirred solution of2-chlorobenzenethiol (2.0 ml) and DMSO (3.7 ml) in dry acetonitrile atroom temperature. After 2 h the white precipitate was filtered andwashed (cold acetonitrile) to give the sub-title compound as a whitesolid (2.27 g).

¹H NMR CDCl₃: δ 7.56 (2H, dd), 7.36 (2H, dd), 7.26-7.14 (4H, m).

ii) 4-bromo-1-[(2-chlorophenyl)sulfonyl]-2-fluorobenzene

The subtitle compound was prepared by the method of example 13 step (ii)using the product of step (i) and 4-bromo-2-fluoroaniline.

¹H NMR CDCl₃: δ 8.38 (1H, dt), 8.10 (1H, dd), 7.60-7.51 (3H, m), 7.45(1H, dd), 7.29 (1H, dd).

iii) 2-chlorophenyl 3,5′-difluoro-2′-methoxybiphenyl-4-yl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (ii) and 5-fluoro-2-methoxybenzene boronicacid which was used directly in step (iv) without furthercharacterisation.

iv) 4′-[(2-chlorophenyl)sulfonyl]-3′,5-difluorobiphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (iii) and boron tribromide.

MS: MM(−ve) 379 (M−H)

v)tert-butyl({4′-[(2-chlorophenyl)sulfonyl]-3′,5-difluorobiphenyl-2-yl}oxy)acetate

The sub-title compound was prepared by the method of example 1 step(iii) using the product of step (iv) which was used directly in step(iv) without further characterisation.

vi)({4′-[(2-chlorophenyl)sulfonyl]-3′,5-difluorobiphenyl-2-yl}oxy)aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (v).

¹H NMR DMSO-d6: δ 8.32 (1H, d), 8.14 (1H, t), 7.82-7.67 (5H, m), 7.36(1H, dd), 7.24 (1H, td), 7.09 (1H, dd), 4.74 (2H, s).

MS: MM(−ve) 437 (M−H).

EXAMPLE 19(2S)-2-{[3′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid

i) 4-bromo-2-chloro-1-(phenylsulfonyl)benzene

The sub-title compound was prepared by the method of example 9 step (1)using 4-bromo-2-chlorobenzenesulfonyl chloride and benzene.

MS: MM(−ve) 331 (M−H).

ii) 3′-chloro-5-fluoro-2-methoxy-4′-(phenylsulfonyl)biphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and 5-fluoro-2-methoxybenzene boronicacid.

¹H NMR DMSO-d6: δ 8.37 (1H, dd), 8.00 (2H, dd), 7.61 (3H, dd), 7.53 (2H,td), 7.07 (1H, ddd), 7.02 (1H, dd), 6.92 (1H, dd), 3.79 (3H, s).

iii) 3′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii).

MS: MM(−ve) 361 (M−H).

iv) methyl(2S)-2-{[3′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoate

The subtitle compound was prepared by the method of example 11 step(vii) using the product of step (iii) and the product of example 11 step(vi).

MS: MM(+ve) 449 (M+H).

v)(2S)-2-{[3′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid

The title compound was prepared by the method of example 11 step (viii)using the product of step (iv).

¹H NMR DMSO-d6: δ 8.32 (1H, d), 7.98-7.96 (3H, m), 7.93 (1H, dd), 7.76(1H, tt), 7.67 (2H, t), 7.35 (1H, dd), 7.23 (1H, td), 7.03 (1H, dd),4.95 (1H, q), 1.42 (3H, d).

MS: MM(−ve) 433 (M−H).

EXAMPLE 20({4-[(3-chlorophenyl)sulfonyl]-2′,5-difluorobiphenyl-2-yl}oxy)aceticacid

i) 1,1′-dithiobis(3-chlorobenzene)

The subtitle compound was prepared by the method of example 11 step (i)using 3-chlorobenzenethiol.

MS: MM(+ve) 287 (M+H).

ii) 1-bromo-4-[(3-chlorophenyl)sulfonyl]-2-fluorobenzene

The subtitle compound was prepared by the method of example 13 step (ii)using the product of step (i) and 4-bromo-3-fluoroaniline.

¹H NMR CDCl₃: δ 7.91 (1H, t), 7.82 (1H, dt); 7.74 (1H, dd), 7.68 (1H,dd); 7.61 (1H, dd), 7.59-7.56 (1H, m), 7.48 (1H, t).

iii) 3-chlorophenyl 2,5′-difluoro-2′-methoxybiphenyl-4-yl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (ii) and 5-fluoro-2-methoxybenzene boronicacid.

MS: APCI(−ve) 393 (M−H).

iv) 4′-[(3-chlorophenyl)sulfonyl]-2′,5-difluorobiphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (iii) and boron tribromide.

MS: APCI(−ve) 381 (M−H)

v)tert-butyl({4′-[(3-chlorophenyl)sulfonyl]-2′,5-difluorobiphenyl-2-yl}oxy)acetate

The sub-title compound was prepared by the method of example 1 step(iii) using the product of step (iv).

¹H NMR DMSO-d6: δ 8.10 (1H, t), 7.98 (2H, dd), 7.55-7.49 (3H, m), 7.45(1H, dd), 7.07-7.02 (2H, m), 6.80 (1H, dd), 4.48 (2H, s), 1.44 (9H, s).

vi)({4′-[(3-chlorophenyl)sulfonyl]-2′,5-difluorobiphenyl-2-yl}oxy)aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (v).

¹H NMR DMSO-d6: δ 8.09 (1H, t), 8.00 (2H, t), 7.77-7.72 (4H, m), 7.32(1H, dd), 7.24 (1H, td), 7.09 (1H, dd), 4.74 (2H, s).

MS: MM(−ve) 437 (M−H).

EXAMPLE 21({2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)aceticacid

i) 2-fluoro-2′-methoxy-5′-methylbiphenyl-4-yl-4-fluorophenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of example 9 step (1) and 5-methyl-2-methoxybenzeneboronic acid.

¹H NMR DMSO-d6: δ 8.00 (2H, ddd), 7.73 (1H, dd), 7.66 (1H, dd), 7.49(1H, dd), 7.24-7.18 (3H, m), 7.01 (1H, d), 6.89 (1H, d), 3.76 (3H, s),2.31 (3H, s).

ii) 2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (i).

MS: MM(−ve) 360 (M−H)

iii)tert-butyl({2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product of step (ii).

MS: MM(−ve) 472 (M−H).

v)({2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.14 (2H, ddd), 7.90 (1H, dd), 7.84 (1H, dd), 7.68(1H, t), 7.50 (2H, dd), 7.20 (1H, dd), 7.09 (1H, s), 6.90 (1H, d), 4.62(2H, s), 2.22 (3H, s).

MS: MM(−ve) 417 (M−H).

EXAMPLE 22{[3′-fluoro-5-methyl-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid

i) 3′-fluoro-2-methoxy-5-methyl-4′-(phenylsulfonyl)biphenyl

The subtitle compound was prepared by the method of example 2 step (ii)using the product of example 2 step (i) and(2-methoxy-5-methylphenyl)boronic acid.

MS: ES+ve 357 (M+1).

ii) 3′-fluoro-5-methyl-4′-(phenylsulfonyl)biphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (i).

MS: APCI−ve 341 (M−1).

iii) tert-butyl{[3′-fluoro-5-methyl-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetate

The subtitle compound was prepared by the method of example 1 step (iii)using the product of step (ii).

MS: APCI−ve 401 (M-[t-butyl]).

iv) {[3′-fluoro-5-methyl-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid

The subtitle compound was prepared by the method of example 1 step (iv)using the product of step (iii).

¹H NMR DMSO-d6: δ 8.06 (1H, t), 7.99 (2H, d), 7.77 (1H, tt), 7.70-7.66(4H, m), 7.23 (1H, d), 7.18 (1H, dd), 6.94 (1H, d), 4.71 (2H, s), 2.27(3H, s).

MS: APCI−ve 399 (M−1).

EXAMPLE 23{[5-chloro-3′,5′-difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid

i) 4-bromo-2,6-difluorophenyl phenyl sulfone

A solution of diphenyl disulphide (1.26 g) and isoamyl nitrite (1.2 ml)in dry acetonitrile (20 ml) was stirred at 50° C.4-bromo-2,6-difluoroaniline (1.0 g) was added portionwise and thereaction mixture was stirred at 60° C. for 2 h and then concentratedunder reduced pressure. The residue (2.1 g) was dissolved in acetic acid(7.5 ml) and hydrogen peroxide (0.7 ml, 30% in aqueous w/w) was addedand the mixture stirred overnight at 100° C. Ice was added, the mixturestirred for a further 30 mins and the beige solid filtered off (0.76 g)and taken through to the next step without further purification.

ii) 5′-chloro-3,5-difluoro-2′-methoxybiphenyl-4-yl phenyl sulfone

The subtitle compound was prepared by the method of example 2 step (ii)using the product of step (i) and 5-chloro-2-methoxybenzene boronic acidwhich was used directly in step (iv) without further characterisation.

MS: MM(−ve) 394 (M−H).

iii) 4′-[(2-chlorophenyl)sulfonyl]-3′,5-difluorobiphenyl-2-ol

The subtitle compound was prepared by the method of example 2 step (iii)using the product of step (ii) and boron tribromide.

MS: MM(−ve) 379 (M−H).

iv) tert-butyl{[5-chloro-3′,5′-difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetate

The sub-title compound was prepared by the method of example 1 step(iii) using the product of step (iii) which was used directly in step(iv) without further purification.

MS: ES(+ve) 495 (M+H).

v) {[5-chloro-3′,5′-difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid

The title compound was prepared by the method of example 1 step (iv)using the product of step (v).

¹H NMR DMSO-d6: δ 8.04 (2H, d), 7.81 (1H, tt), 7.71 (2H, t), 7.65 (1H,s), 7.62 (1H, s), 7.54 (1H, d), 7.46 (1H, dd), 7.12 (1H, d), 4.80 (2H,s).

MS: MM(−ve) 437 (M−H).

Rat Pharmacokinetic Data

IV and PO Rat Pharmacokinetic Studies

Test samples are made up at 1 mg/ml in an appropriate solvent andadministered to Sprague Dawley rats either via the tail vein (IV, 1ml/kg) or via the mouth (PO, 3 ml/kg). Blood samples are removed fromthe tail vein (reverse side to IV administration) at a series of timepoints and placed on ice. Blood samples are centrifuged and the plasmaremoved for analysis. Plasma samples are then analysed using MS/MS andconcentrations of parent compound determined from a standard curve. Theplasma concentration-time plot is analysed using the commercial softwareWinNonLin 3.1 (Pharsight, Mountain View, Calif.). Pharmacokineticparameters such as clearance, volume of distribution and half-life aredetermined. Compounds of formula (I) have a half life>2.5 hours.

Pharmacological Data

Ligand Binding Assay

[³H]PGD₂ was purchased from Perkin Elmer Life Sciences with a specificactivity of 100-210 Ci/mmol. All other chemicals were of analyticalgrade.

HEK cells expressing rhCRTh2/Gα16 were routinely maintained in DMEMcontaining 10% Foetal Bovine Serum (HyClone), 1 mg/ml geneticin, 2 mML-glutamine and 1% non-essential amino acids. For the preparation ofmembranes, the adherent transfected HEK cells were grown to confluencein two layer tissue culture factories (Fisher, catalogue numberTKT-170-070E). Maximal levels of receptor expression were induced byaddition of 500 mM sodium butyrate for the last 18 hours of culture. Theadherent cells were washed once with phosphate buffered saline (PBS, 50ml per cell factory) and detached by the addition of 50 ml per cellfactory of ice-cold membrane homogenisation buffer [20 mM HEPES (pH7.4), 0.1 mM dithiothreitol, 1 mM EDTA, 0.1 mM phenyl methyl sulphonylfluoride and 100 μg/ml bacitracin]. Cells were pelleted bycentrifugation at 220×g for 10 minutes at 4° C., re-suspended in halfthe original volume of fresh membrane homogenisation buffer anddisrupted using a Polytron homogeniser for 2×20 second bursts keepingthe tube in ice at all times. Unbroken cells were removed bycentrifugation at 220×g for 10 minutes at 4° C. and the membranefraction pelleted by centrifugation at 90000×g for 30 minutes at 4° C.The final pellet was re-suspended in 4 ml of membrane homogenisationbuffer per cell factory used and the protein content determined.Membranes were stored at −80° C. in suitable aliquots.

All assays were performed in Corning clear bottomed, white 96-well NBSplates (Fisher). Prior to assay, the HEK cells membranes containingCRTh2 were coated onto SPA PVT WGA beads (Amersham). For coatingmembranes were incubated with beads at typically 25 μg membrane proteinper mg beads at 4° C. with constant agitation overnight. (The optimumcoating concentrations were determined for each batch of membranes) Thebeads were pelleted by centrifugation (800×g for 7 minutes at 4° C.),washed once with assay buffer (50 mM HEPES pH 7.4 containing 5 mMmagnesium chloride) and finally re-suspended in assay buffer at a beadconcentration of 10 mg/ml.

Each assay contained 20 μl of 6.25 nM [³H]PGD₂, 20 μl membrane saturatedSPA beads both in assay buffer and 10 μl of compound solution or13,14-dihydro-15-keto prostaglandin D₂ (DK-PGD₂, for determination ofnon-specific binding, Cayman chemical company). Compounds and DK-PGD₂were dissolved in DMSO and diluted in the same solvent to 100× therequired final concentration. Assay buffer was added to give a finalconcentration of 10% DMSO (compounds were now at 10× the required finalconcentration) and this was the solution added to the assay plate. Theassay plate was incubated at room temperature for 2 hours and counted ona Wallac Microbeta liquid scintillation counter (1 minute per well).Compounds of formula (I) have a pIC₅₀ value of >8.5.

Specifically example 7 has a pIC₅₀ value of 8.5; example 8 has a pIC₅₀value of 8.8; example 15 has a pIC₅₀ value of 8.8.

The invention claimed is:
 1. A compound of formula (I) or apharmaceutically acceptable salt thereof:

wherein A and D are independently selected from hydrogen, halogen,nitrile, C₁₋₃ alkyl, and C₁₋₃ alkoxy, wherein the latter 2 groups can beoptionally substituted by one or more halogen; X is halogen, or C₁₋₃alkyl which is optionally substituted by one or more halogen; Y is abond; Z is aryl or heteroaryl substituted by one or more substituentsselected from hydrogen, halogen, nitrile, C₁₋₆ alkyl, C₁₋₆ alkoxy,SO₂C₁₋₆ alkyl, and heteroaryl, wherein the latter four groups may beoptionally substituted by one of more halogen, nitrile or SO₂C₁₋₆ alkyl;R¹ and R² are independently a hydrogen, or a C₁₋₃ alkyl group; or R¹ andR² together can form a 3-8 membered ring optionally containing one ormore groups selected from O, S, and NR³ and itself optionallysubstituted by one or more C₁-C₃ alkyl; and R³ is hydrogen or C₁-C₆alkyl.
 2. A compound or a pharmaceutically acceptable salt thereof,according to claim 1, wherein X is chloro, fluoro or methyl.
 3. Acompound or a pharmaceutically acceptable salt thereof, according toclaim 1, wherein the group SO₂—Y—Z is at the 4-position of the phenylring, according to the structure:


4. A compound or a pharmaceutically acceptable salt thereof, accordingto claim 1, wherein the group SO₂—Y—Z is at the 4-position of the phenylring, and is ortho to both A and D, according to the structure:


5. A compound or a pharmaceutically acceptable salt thereof, accordingto claim 1, wherein the group SO₂—Y—Z is at the 4-position of the phenylring, and ortho to A and meta to D, according to the structure:


6. A compound or a pharmaceutically acceptable salt thereof, accordingto claim 1, wherein A and D are independently hydrogen, halogen or C₁₋₃alkyl optionally substituted by one or more halogen.
 7. A compound or apharmaceutically acceptable salt thereof, according to claim 1, whereinA is hydrogen, halogen or CF₃.
 8. A compound or a pharmaceuticallyacceptable salt thereof, according to claim 1, wherein D is hydrogen,halogen or methyl.
 9. A compound or a pharmaceutically acceptable saltthereof, according to claim 1, wherein A and D are independentlyselected from hydrogen and halogen.
 10. A compound or a pharmaceuticallyacceptable salt thereof, according to claim 1, wherein R¹ and R² areindependently hydrogen or C₁₋₃ alkyl.
 11. A compound or apharmaceutically acceptable salt thereof, according to claim 1, whereinR¹ and R² are independently hydrogen or methyl.
 12. A compound accordingor a pharmaceutically acceptable salt thereof, to claim 1, wherein Z isphenyl optionally substituted by halogen or C₁₋₆ alkoxy.
 13. A compoundor a pharmaceutically acceptable salt thereof, according to claim 1,wherein Z is phenyl optionally substituted by halogen.
 14. A compound ora pharmaceutically acceptable salt thereof, according to claim 1,wherein Z is phenyl optionally substituted by fluoro.
 15. A compound ora pharmaceutically acceptable salt thereof, of formula (I) according toclaim 1, selected from the group consisting of:{[5-Chloro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid;{[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid;(2S)-2-{[3′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid; {[2′,5-Difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid;{[5-Chloro-2′-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}acetic acid;{[5-fluoro-4′-(phenylsulfonyl)-3′-(trifluoromethyl)biphenyl-2-yl]oxy}aceticacid;(2S)-2-({5-chloro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid;(2S)-2-({5-chloro-2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid;(2S)-2-({3′,5-difluoro-4′-[(2-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid;(2S)-2-({3′,5-difluoro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid;(2S)-2-({3′,5-difluoro-4′-[(3-fluorophenyl)sulfonyl]biphenyl-2-yl}oxy)propanoicacid;({5-chloro-4′-[(4-fluorophenyl)sulfonyl]-2′-methylbiphenyl-2-yl}oxy)aceticacid;(2S)-2-{[2′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid;({3′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)aceticacid; ({5-chloro-4′-[(4-methoxyphenyl)sulfonyl]biphenyl-2-yl}oxy)aceticacid;({4′-[(2-chlorophenyl)sulfonyl]-3′,5-difluorobiphenyl-2-yl}oxy)aceticacid;(2S)-2-{[3′-chloro-5-fluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}propanoicacid;({4′-[(3-chlorophenyl)sulfonyl]-2′,5-difluorobiphenyl-2-yl}oxy)aceticacid;({2′-fluoro-4′-[(4-fluorophenyl)sulfonyl]-5-methylbiphenyl-2-yl}oxy)aceticacid; {[3′-fluoro-5-methyl-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid; and{[5-chloro-3′,5′-difluoro-4′-(phenylsulfonyl)biphenyl-2-yl]oxy}aceticacid.16. The compound or a pharmaceutically acceptable salt thereof, offormula (I) according to claim 1, wherein the compound is:


17. The compound or a pharmaceutically acceptable salt thereof, of claim16, wherein R¹ and R² are hydrogen; X is halogen; A is hydrogen; D ishalogen; and Z is aryl substituted with halogen.
 18. The compound or apharmaceutically acceptable salt thereof, according to claim 17, whereinX is chloro.
 19. The compound or a pharmaceutically acceptable saltthereof according to claim 18, wherein D is fluoro.
 20. The compound ora pharmaceutically acceptable salt thereof, according to claim 19,wherein Z is phenyl substituted with fluoro.
 21. A pharmaceuticalcomposition comprising a compound of formula (I) according to claim 1,or a pharmaceutically acceptable salt thereof, in association with apharmaceutically acceptable adjuvant, diluent or carrier.